It has conventionally been typical for semiconductor laser elements having stripe structures to be manufactured as described in Non Patent Literature 1, for example.
That is, an object to be processed in which a plurality of semiconductor laser parts to become semiconductor laser elements are arranged in a two-dimensional matrix is initially prepared. Then, the object is scratched with a scriber such as a diamond cutter along end parts of lines to cut extending orthogonal to a stripe direction between the semiconductor laser parts (primary scribing). Subsequently, the object is cleaved along the lines to cut from thus formed scratches acting as a start point, so as to yield a plurality of bars each having a plurality of semiconductor laser parts arranged one-dimensionally.
Thereafter, the cleavage surfaces of the bars orthogonal to the stripes are coated with dielectric films which become protective films or reflection control films. Then, each bar is scratched with a scriber such as a diamond cutter along the lines to cut extending along the stripe direction between the semiconductor laser parts (secondary scribing). Subsequently, the bar is cleaved along the lines to cut from the resulting scratches acting as a start point, whereby a plurality of semiconductor laser elements are obtained.
The following is the reason why a plurality of bars are obtained by cleaving the object from scratches formed by the primary scribing acting as a start point and then each of the plurality of bars is subjected to the secondary scribing. That is, if the object is initially subjected to both of the primary scribing and secondary scribing, the scratches formed by the secondary scribing may affect the object cleaving from the scratches made by the primary scribing, thereby failing to yield bars with precise cleavage surfaces.    Non Patent Literature 1: Hirata, Shoji, “Understanding Fundamentals and Applications of Semiconductor Lasers”, 3d ed., CQ Publishing Co., Ltd., Aug. 1, 2004, pp. 121-124